/*
 * Copyright 2008 - 2009 Lars Heuer (heuer[at]semagia.com). All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.semagia.atomico.server.feed.impl;

import java.net.URI;
import java.util.Collections;
import java.util.Set;

import com.semagia.atomico.dm.IAuthor;
import com.semagia.atomico.dm.IAuthorAwareEntity;
import com.semagia.atomico.dm.IEntity;
import com.semagia.atomico.dm.ISummaryAwareEntity;

/**
 * 
 * 
 * @author Lars Heuer (heuer[at]semagia.com) <a href="http://www.semagia.com/">Semagia</a>
 * @version $Rev: 117 $ - $Date: 2010-11-06 14:39:35 +0000 (Sat, 06 Nov 2010) $
 */
abstract class AbstractLinkAwareEntity<T extends IEntity> implements
        ILinkAwareEntity, IAuthorAwareEntity, ISummaryAwareEntity {

    private final String _link;

    protected final T _entity;

    protected AbstractLinkAwareEntity(final T entity, final URI link) {
        if (entity == null) {
            throw new IllegalArgumentException("The entity must not be null");
        }
        if (link == null) {
            throw new IllegalArgumentException("The link must not be null.");
        }
        _link = link.toASCIIString();
        _entity = entity;
    }

    /*
     * (non-Javadoc)
     * 
     * @see com.semagia.atomico.feed.ILinkAwareEntry#getLink()
     */
    @Override
    public String getLink() {
        return _link;
    }

    /*
     * (non-Javadoc)
     * 
     * @see com.semagia.atomico.dm.IEntity#getAuthors()
     */
    @Override
    public Set<IAuthor> getAuthors() {
        return _entity instanceof IAuthorAwareEntity 
                    ? ((IAuthorAwareEntity) _entity).getAuthors() 
                    : Collections.<IAuthor> emptySet();
    }

    /*
     * (non-Javadoc)
     * 
     * @see com.semagia.atomico.dm.IEntity#getSummary()
     */
    @Override
    public String getSummary() {
        return _entity instanceof ISummaryAwareEntity 
                    ? ((ISummaryAwareEntity) _entity).getSummary() 
                    : null;
    }

    /*
     * (non-Javadoc)
     * 
     * @see com.semagia.atomico.dm.IEntity#getId()
     */
    @Override
    public String getId() {
        return _entity.getId();
    }

    /*
     * (non-Javadoc)
     * 
     * @see com.semagia.atomico.dm.IEntity#getTitle()
     */
    @Override
    public String getTitle() {
        return _entity.getTitle();
    }

    /*
     * (non-Javadoc)
     * 
     * @see com.semagia.atomico.dm.IEntity#getUpdated()
     */
    @Override
    public long getUpdated() {
        return _entity.getUpdated();
    }

}
